Located on the Austrian side of the Loibl Pass are several memorial plaques dedicated to the prisoners of the Loibl Concentration Camp North, who had to perform forced labour in the construction of the Loibl tunnel.

Loibl, 1944, Watchtower with guards, Gedenkstätte Loibl KZ Nord

Loibl, 2003, Foundations of the former wash barrack, Peter Gstettner

In the spring of 1943, the SS began preparing the construction of a road tunnel and an access road through the Loibl Pass, an Alpine pass between Austria and what is today Slovenia. Civil workers and an increasing number of prisoners from the Mauthausen concentration camp were involved in the construction. In all, over 1,600 forced labourers were deployed in the Loibl Pass. The prisoners were accommodated in a concentration camp, which they were for the most part forced to build themselves. The camp was divided into two parts: the Concentration Camp South (today on Slovenian territory) and the Concentration Camp North on the Austrian side of the mountain pass. In December 1944, after twenty months of construction, the first Wehrmacht vehicles could use the over 1,500 metre long tunnel. Only a few months later, the tunnel became an important retreat route from the Balkans for the Wehrmacht.
On April 15, 1945, the SS dissolved the Loibl Concentration Camp North due to intensified partisan attacks and transported most of the prisoners to the south camp. Between May 7 and 8, 1945, camp inmates and partisans liberated the camp and took the SS guards captive.

Loibl, 1944, Watchtower with guards, Gedenkstätte Loibl KZ Nord

Loibl, 2003, Foundations of the former wash barrack, Peter Gstettner

Until May 1945, over 1,500 people were incarcerated by the SS in the north and south Loibl concentration camps combined. Most of them were political prisoners from the Mauthausen concentration camp.
Frenchmen and Poles constituted the largest prisoner groups at the Loibl concentration camps. Among the inmates were also Russians, Yugoslavs, Germans, Italians, Czechs, Hungarian Jews, Norwegians, Luxembourgers, Spaniards and others.
Over 30 prisoners died during construction work at the Loibl Pass or were killed by SS guards. The SS had approximately 300 ill and weak prisoners transported back to Mauthausen where most of them were murdered.

After 1945, the premises of the former Loibl Concentration Camp North were privately owned and the remains of the camp were cleared. The Loibl Pass, which at the time connected Austria and Yugoslavia, remained closed until 1950. In 1967, Austria opened the renovated Loibl tunnel for traffic. On this occasion, the »Amicale de Mauthausen« association set up a memorial plaque dedicated to the forced labourers of the Loibl concentration camp.
In 1995, the regional initiative »Mauthausen Aktiv Kärnten/Koroška« set up two large commemorative panels which display information about the history of the camp and honour the victims of forced labour.
On June 11, 2005, Polish state representatives unveiled a memorial plaque to the Polish forced labourers who perished on the Loibl Pass.